Tool with shock absorbing means



Feb. 15, 1955 E. J. BONNESEN 2,702,060

TOOL wrm SHOCK ABSORBING MEANS Filed Dec. 17, 1952 INVENTOR 'ELMER J.BQNNESEN BY 10 ATTORN Y United States Patent TOOL WITH SHOCK ABSORBINGMEANS Elmer J. Bonnesen, Summit, N. J., assignor of one-halt to HowardD. Brown, Westfield, N. J.

Application December 17, 1952, Serial No. 326,501

1 Claim. (Cl. 145-29) This invention relates to handled instruments ortools having a blow head and commonly referred to as hammers. Moreparticularly, the invention deals with the provision of means forabsorbing shock between the head and handle, particularly in tools ofthe character described in which heavy blows are struck and, wherein,the likelihood of shock transmission prevails.

The novel features of the invention will be best understood from thefollowing description, when taken together with the accompanyingdrawing, in which certain embodiments of the invention are disclosed,and in which, the separate parts are designated by suitable referencecharacters in each of the views and, in which the drawing is'a side viewof a sledge hammer made according to my invention, with parts of theconstruction broken away and parts in section.

In the drawing, I have shown what is generally termed a sledge hammer,comprising an elongated handle men;- ber 1 and a sledge or other head 2.The handle member is in the form of a rod having a collar 3 adjacent theouter end thereof, the outer end 4 being slightly reduced and beingarranged in a bushing 5 of yielding shock absorbing material. Thebushing 5 is arranged in an aperture 6 formed centrally or substantiallycentrally of the hammer head 2, the aperture being enlarged, as seen at7, where it opens through the outer surface 8 of the head; the bushing 5is flanged, as seen at 9, to fit in the enlargement 7.

The end portion 4 has a retaining member 10 which fits in the recess 7and is countersunk within the surface 8, the member 10 serving to holdthe head 2 against displacement from the handle member. In theconstruction shown, the member 10 is in the form of a rivet head on theend portion 4 of the handle member. It will also be apparent that thebushing 5 includes a flange portion 11 between the surface 12 of thehead 2 and the flange 3.

The bushing 5 may be composed of any shock absorbing material, such forexample, as rubber or synthetic rubbers of any type or kind and it ispreferred that a material be employed which will withstand exposure toweather and rough usages while, at the same time, providing thecushioning effect which is desired. It will be apparent that the bushing5 will be arranged in the aperture or bore 6 and recess 7 prior toattachment of the handle member with the head and bushing.

The inner or hand grip end portion of the sleeve or hammer is preferablyroughened or knurled, as seen at 13, to provide a binding surface for arubber or synthetic rubber hand grip 14 which can be moulded on the handgrip or cemented or otherwise secured thereto.

By virtue of the structure employed, it will be apparent that, in theuse of the hammer, in striking a blow, the shock of the blow is directlytaken up through the yielding bushing which is employed and this shockis thus not transmitted to the handle member, at least not to anynoticeable or appreciable degree. Further, by utilizing the yieldinghand grip, any shock which may be transmitted to the handle member wouldbe taken up through the hand grip, thus producing an outstanding reliefto the operator using hammers of the type and kind under consideration.

It will be understood that the shock absorbing characteristics, as heredisclosed, can be applied to hammers of various types and kinds and suchuses will minimize the physical fatigue which is usually brought aboutby the shock transmitted to the hand and arm and, in fact, the rest ofthe body in the operation of tools of this type and kind.

With hammers as usually constructed, a positivev and firm rigid couplinghas been provided between the handle member and the hammer head and theshock of a blow has been transmitted directly to the handle and, thus,to the operator in handling the tool. At times, these shocks have beenamplified, particularly when the tool strikes an object in an unbalancedmanner or, in other words, 01f center with respect to the head of thehammer. Here again, such amplified shocks are absorbed through the shockabsorbing medium such as the bushing 5 in the manner herein disclosed.

It will be understood that, by providing the flanged ends 9 and 11 onthe bushing, any shock tending to shift the axis of the head withrespect to the axis of the handle member will be taken up through theflanges 9 and 11.

Having fully described my invention, what I claim as new and desire tosecure by Letters Patent is:

A tool of the class described, comprising an elongated handle memberhaving a large diameter collar inwardly of and adjacent one end thereof,a head mounted on the handle member outwardly of said collar, means atsaid end of the handle member securing the head against displacementfrom the handle member, an annular bushing of shock absorbing materialspacing the handle member from said head, said bushing including shockabsorbing flanges disposed between the head, collar and said headsecuring means, the other end of the handle member having a roughenedsurface, and a hand-grip portion of shock absorbing material fixed tosaid roughened surface.

References Cited in the file of this patent UNITED STATES PATENTS222,825 Isham Dec. 23, 1879 1,435,851 Isham Nov. 14, 1922 1,508,395Isham Sept. 16, 1924 1,581,647 Layton Apr. 20, 1926 1,609,117 HansenNov. 30, 1926 1,632,227 Halsey June 14, 1927 2,067,751 Beegle Jan. 12,1937 2,656,225 Saylor Oct. 20, 1953

